The Long and Short of Coupling and Uncoupling via 2D IR Spectroscopy.

J Phys Chem B

Department of Chemistry, University of Nevada, Reno, 1664 N. Virginia Street, Reno, Nevada 89557, United States.

Published: November 2024

AI Article Synopsis

  • Scientists have faced challenges in understanding dynamic structural changes and functional movements in biological systems for decades.
  • 2D IR spectroscopy, using vibrational coupling with probe pairs, has helped reveal the structural dynamics in processes like peptide folding, ion transport, and drug-protein interactions.
  • This perspective discusses various vibrational coupling treatments and models, assessing the effectiveness of different probe pairs to provide insights into molecular dynamics and structural reactions at an atomic level.

Article Abstract

Determining dynamic structural changes along with the functional movements in biological systems has been a significant challenge for scientists for several decades. Utilizing vibrational coupling with the aid of 2D IR probe pairs has aided in uncovering structural dynamics and functional roles of chemical moieties involved in actions such as membrane peptide folding and transport, ion and water transport, and drug-protein interactions. Both native and non-native vibrational probe pairs have been developed for infrared studies, and their efficacy has been tested in various systems. With these probe pairs, 2D IR spectroscopy captures frozen snapshots of the structural events involved in biological function through vibrational coupling and correlated spectral diffusion. In this Perspective, different treatments of vibrational coupling and coupling models will be addressed, and a review of some of the specific vibrational probe pairs used to study these coupling mechanisms is presented. Overall, the intrinsic molecular dynamics detected on these ultrafast time scales will provide an atomic level view of how chosen structures traverse reaction paths. Thus, it is important to evaluate and assess the accuracy of the different vibrational coupling models and their consistency with the prediction of different molecular structures.

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http://dx.doi.org/10.1021/acs.jpcb.4c05511DOI Listing

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